This work reports the completion and annotation of the genome sequence of Corynebacterium pseudotuberculosis I19, isolated from an Israeli dairy cow with severe clinical mastitis. To present the whole-genome sequence, a de novo assembly approach using 33 million short (25-bp) mate-paired SOLiD reads only was applied. Furthermore, the automatic, functional, and manual annotations were attained with the use of several algorithms in a multistep process.
1 December 2015 in Diagnostic Microbiology and Infectious Disease
Pseudomonas aeruginosa is an opportunistic pathogen causing different types of infections, particularly in intensive care unit patients. Characteristics that favor its persistence artificial environments are related to its high adaptability, wide arsenal of virulence factors and resistance to several antimicrobial classes. Among the several virulence determinants, T3SS stands as the most important due to the clinical impact of exoS and exoU genes in patient’s outcome. The molecular characterization of P. aeruginosa isolates helps in the comprehension of transmission dynamics and enhance knowledge of virulence and resistance roles in infection process. In the present study, we investigated virulence and resistance properties and the genetic background of P. aeruginosa isolated from ICUs patients at a referral hospital in Brazilian Amazon. A total of 54 P. aeruginosa isolates were characterized by detecting 19 virulence-related genes, antimicrobial susceptibility testing, molecular detection of β-lactamase-encoding genes and genotyping by MLST and rep-PCR. Our findings showed high prevalence of virulence-related markers, where 53.7% of the isolates presented at least 17 genes among the 19 investigated (P = 0.01). The rare exoS+/exoU+ cytotoxic virulotype was detected in 55.6% of isolates. Antimicrobial susceptibility testing revealed percentages of antibiotic resistance above 50% to carbapenems, cephalosporins and fluoroquinolones associated to MDR/XDR isolates. Isolates harboring both blaSPM-1 and blaOXA genes were also detected. Genotyping methods demonstrated a wide genetic diversity of strains spread among the different intensive care units, circulation of international MDR/XDR high-risk clones (ST111, ST235, ST244 and ST277) and emergence of seven novel MLST lineages. Finally, our findings highlight the circulation of strains with high virulence potential and resistance to antimicrobials and may be useful on comprehension of pathogenicity process, treatment guidance and establishment of strategies to control the spread of epidemic P. aeruginosa strains.
1 June 2016 in Revista da Sociedade Brasileira de Medicina Tropical
Introduction: The spread of multidrug-resistant Pseudomonas aeruginosa in Brazilian hospitals has greatly impacted upon the morbidity and mortality of individuals in intensive care units. Given the lack of information regarding the dynamics of multidrug resistance in northern Brazil, we analyzed the clinical and microbiological features of nosocomial infections caused by P. aeruginosa. Methods: Between January 2010 and March 2012, we conducted a retrospective cohort study of P. aeruginosa isolates from 54 patients who were hospitalized in intensive care units. The clinical and epidemiologic variables were analyzed, including the patients' demographic data and comorbidities, and the lengths of the intensive care unit stays, the classification of the infections as nosocomial, the use of invasive procedures, antimicrobial therapy, and the patients' outcomes. We undertook susceptibility tests, molecular detection of the metallo-beta-lactamase genes, and genotypic analyses of the isolates using the repetitive element-polymerase chain reaction. Results: Multidrug resistance occurred most frequently among isolates from adults who had been hospitalized for an average of 87.1 days. The use of mechanical ventilation and urinary catheters were risk factors for infection. The four isolates that harbored the blaSPM-1-like gene showed >95% genetic similarity. Conclusions: This study's findings show that P. aeruginosa has a high death rate, and that inadequate treatment and invasive procedures are risk factors for infection. This is the first report describing the detection of the blaSPM-1-like gene in northern Brazil. These results highlight the need for better monitoring and a greater understanding of nosocomial infections and their public health impacts.
Lack of routine surveillance in countries endemic for bovine tuberculosis (TB) and limited laboratory support contributes to the inability to differentiate theMycobacterium tuberculosisComplex species, leading to an underestimated burden of the disease. Here, Whole-Genome Sequencing ofMycobacterium bovisisolated from tissues with TB-like lesions obtained from cattle and buffalos at Marajó Island, Brazil, demonstrates that recent transmission ofM. bovisis ongoing at distinct sites. Moreover, theM. bovisepidemiology in this setting is herein found to be dominated by an endemic and unique clade composed of strains evolved from a common ancestor that are now genetically differentiated from otherM. bovisclades. Additionally, envisioning a rapid strain differentiation and tracing across multiple settings, 28 globally validated strain-specific SNPs were identified, three of which considered as robust markers for theM. bovisMarajó strain. In conclusion, this study contributes with data regarding the identification of a novelM. bovisphylogenetic clade responsible for ongoing transmission events in both cattle and buffalo species in Brazil, provides a framework to investigate the dissemination of this highly prevalent strain and, holds the potential to inform TB control strategies that may help to prevent the spread of bovine and zoonotic TB.